The quality of air flow within a vehicle is clearly an important consideration with respect to the health and comfort of the occupants. As may be appreciated, air pollution within the vehicle may be the result of atmospheric pollution and solid particulate that may accumulate on roadways. In addition, vehicular air pollution can be the direct result of the volatile organic and/or inorganic contaminants that are associated with vehicle operation such as vehicle exhaust that can concentrate in relatively high density traffic locations. In addition, environmental pollution in the form of volatile organic compounds has become a growing concern.
With regards to vehicular air filtration, one long-standing issue is that with respect to air filtration, the size and configurations available in the engine compartment impacts the size and configuration of the air filter. In that sense, air filtration is often times limited to a relatively compact design requirements, which in turn can lead to reduced efficiency in air filtration and the ability to provide the occupants with a cabin air environment that is more comfortable and relatively free of airborne contaminants.
Furthermore, due to the increasing air pollution, increasingly more pollutants are present in the environment of a motor vehicle so the motor vehicle cabin filter is exposed to a higher concentration of contaminants. These pollutants can be, for example, dust and soot particles as well as pollen, bacterial spores and fungal spores, bacteria and fungi. Some metabolic products of the microorganisms are known to constitute allergic substances for the human respiratory system. In some individuals, they can cause asthma attacks and possibly an immunological defense reaction.
In addition, while the efficiency of filters depends in particular on the surface area of the filter that is exposed to air flow, for motor vehicle cabin filters primarily zigzag-shaped folded filter media are used that are also often referred to as pleated filter media. In this way, due to the folding of the employed filter medium, depending on the height of the folds and the fold spacing of the various fold sections of the filter medium, an effective enlargement of the filter surface area flowed through by the air flow can be provided. However, as noted, given issues with available spacing in fossil fuel type engines, the use of pleated filters of relatively restricted size has still limited the ultimate efficiency that may be provided to vehicle occupants.